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Niwa, Masakazu; Shimada, Koji; Sueoka, Shigeru; Ishihara, Takanori; Hakoiwa, Hiroaki; Asamori, Koichi; Murakami, Osamu; Fukuda, Shoma; Ogita, Yasuhiro; Kagami, Saya; et al.
JAEA-Research 2024-013, 65 Pages, 2024/11
This annual report documents the progress of research and development (R&D) in the 2nd fiscal year of the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028) to provide the scientific base for assessing geosphere stability for long-term isolation of high-level radioactive waste. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques. The current status of R&D activities with previous scientific and technological progress is summarized.
Niwa, Masakazu; Shimada, Akiomi; Asamori, Koichi; Sueoka, Shigeru; Komatsu, Tetsuya; Nakajima, Toru; Ogata, Manabu; Uchida, Mao; Nishiyama, Nariaki; Tanaka, Kiriha; et al.
JAEA-Review 2024-035, 29 Pages, 2024/09
This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency (JAEA), in fiscal year 2024. The objectives and contents of this research are described in detail based on the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028). In addition, the background of this research is described from the necessity and the significance for site investigation and safety assessment, and the past progress. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.
Ogata, Manabu; Komatsu, Tetsuya; Nakanishi, Toshimichi*
Earth, Planets and Space (Internet), 76, p.123_1 - 123_11, 2024/09
Times Cited Count:0 Percentile:0.00(Geosciences, Multidisciplinary)Marine terraces developed along the southeastern coast of Kii Peninsula, southwestern Japan, face a seismogenic region along the Nankai Trough. We determined the emergence age of one of these marine terraces by using feldspar OSL dating of the marine terrace sediments. The target marine terrace has previously been correlated with MIS 5e on the basis of morphostratigraphy. Samples for pIRIR dating were obtained from foreshore deposits of the marine terrace. pIRIR signals were measured at 150 C (pIRIR
) and 225
C (pIRIR
). These results show that the surface of the marine terrace corresponds to MIS 5e rather than MIS 5c or 7, which is consistent with the chronological framework based on the morphological features of the terraces in this study area.
Niwa, Masakazu; Shimada, Koji; Sueoka, Shigeru; Fujita, Natsuko; Yokoyama, Tatsunori; Ogita, Yasuhiro; Fukuda, Shoma; Nakajima, Toru; Kagami, Saya; Ogata, Manabu; et al.
JAEA-Review 2023-017, 27 Pages, 2023/10
This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency (JAEA), in fiscal year 2023. The objectives and contents in fiscal year 2023 are described in detail based on the JAEA 4th Medium- and Long-term Plan (fiscal years 2022-2028). In addition, the background of this research is described from the necessity and the significance for site investigation and safety assessment, and the past progress. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.
Niwa, Masakazu; Shimada, Koji; Sueoka, Shigeru; Ishihara, Takanori; Ogawa, Hiroki; Hakoiwa, Hiroaki; Watanabe, Tsuyoshi; Nishiyama, Nariaki; Yokoyama, Tatsunori; Ogata, Manabu; et al.
JAEA-Research 2023-005, 78 Pages, 2023/10
This annual report documents the progress of research and development (R&D) in the 1st fiscal year of the Japan Atomic Energy Agency 4th Medium- and Long-term Plan (fiscal years 2022-2028) to provide the scientific base for assessing geosphere stability for long-term isolation of high-level radioactive waste. The plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques. The current status of R&D activities with previous scientific and technological progress is summarized.
Ogata, Manabu; King, G. E.*; Herman, F.*; Sueoka, Shigeru
Earth and Planetary Science Letters, 591, p.117607_1 - 117607_14, 2022/08
Times Cited Count:4 Percentile:45.21(Geochemistry & Geophysics)Optically stimulated luminescence (OSL)-thermometry can be used to reconstruct the thermal structure in slowly denuded regions where infrared stimulated luminescence (IRSL) signals of samples obtained from deep boreholes are measured and evaluated with depth. Until now, only one study has explored this approach, using a target mineral of Na-feldspar. In this study, we applied multi-OSL-thermometry to K-feldspar obtained from deep borehole core samples (MIZ-1) drilled at the Tono region, central Japan, which is a well-documented thermally stable crustal environment. The inverted temperature for the IRSL 50 C of the samples at a depth of
1 km (
40
C) were consistent with the in-situ temperature. The results suggest that the application of OSL-thermometry to K-feldspar in a borehole is useful to reconstruct the paleothermal condition.
Nakanishi, Toshimichi*; Komatsu, Tetsuya; Ogata, Manabu; Kawamura, Makoto; Yasue, Kenichi*
Gekkan Chikyu "Kiso deta Kara Kangaeru Dai Yonkigaku No Shintenkai-I" Gogai No.71, p.148 - 155, 2022/02
The formation process of terrace topography was investigated by observing and analyzing boring core samples collected in the middle reaches of the Kumano River. It was assumed that the older terrace topography was distributed higher than the current riverbed surface. However, since tributary debris flow deposits may be thickly distributed beneath the old gyre river valley, care must be taken when using the surface of the ground as an index of uplift and erosion.
Nakajima, Toru; Fukuda, Shoma; Ogata, Manabu; Sueoka, Shigeru
Fuisshon, Torakku Nyusureta, (34), p.25 - 26, 2021/12
The 17th International Conference on Thermochronology (Thermo2021) was held on September 12-17, 2021 at the Eldorado Resort in downtown Santa Fe, New Mexico, USA. Due to the social situation and the spread of the COVID-19, the event had been postponed. In this paper, I report on the circumstances surrounding our participation in the conference, the contents and trends of the presentations made at the conference, and the tasks for the 2023 and 2025 conferences.
Ogata, Manabu; Komatsu, Tetsuya; Nakanishi, Toshimichi
Dai Yonki Kenkyu, 60(2), p.27 - 41, 2021/06
no abstracts in English
Ogata, Manabu; Sueoka, Shigeru
Radioisotopes, 70(3), p.159 - 172, 2021/03
no abstracts in English
Ogata, Manabu; King, G.*; Herman, F.*; Sueoka, Shigeru; Yamada, Ryuji*; Omura, Kentaro*
no journal, ,
no abstracts in English
Ishihara, Takanori*; Hosoya, Takashi*; Ueki, Tadamasa*; Ogata, Manabu
no journal, ,
no abstracts in English
Ogata, Manabu; King, G. E.*; Herman, F.*; Yamada, Ryuji*; Omura, Kentaro*; Sueoka, Shigeru
no journal, ,
Optically stimulated luminescence (OSL) thermochronometry is a tool for constraining cooling histories in low-temperature domains (several tens of degree Celsius) during the past 10-100 kyr. This method is currently applied only to rapidly denuded regions (about 5 mm/yr), because luminescence signals in slowly denuded regions saturate before the rocks are exhumated to the surface. However, cooling histories in slowly denuded regions may be constrained if unsaturated samples are obtained from deep boreholes. We applied multi-OSL-thermochronometry to the deep borehole core drilled at the Rokko Mountains, Japan, where slow denudation rates (0.1-1.0 mm/yr) are expected from previous studies. We used the Kabutoyama core collected by National Research Institute for Earth Science and Disaster Resilience. The total length of Kabutoyama core is 1,313 m and we collected the samples at 408, 642, 818 and 1048 m for OSL-thermochronometry. We found that the sample temperatures remained around the present ambient temperature at each depth for the last 0.1 Myr, indicating that the Rokko Mountains is topographically stable, which was consistent with previous findings. Thus, the thermal denudation history of slowly denuded regions may be constrained by multi-OSL-thermochronometry using samples from deep borehole cores. However, the denudation rates in the Rokko Mountains were too low and could not be determined by this method.
Ogata, Manabu; King, G. E.*; Herman, F.*; Sueoka, Shigeru
no journal, ,
no abstracts in English
Tsukahara, Yuzuko; Ogata, Manabu; Kawamura, Makoto; Kanno, Mizuho*; Nishiyama, Nariaki; Sueoka, Shigeru; Nakanishi, Toshimichi*; Komatsu, Tetsuya
no journal, ,
One hundred thousand-year-scale uplift rate of the Japanese mountains is estimated mainly based on the Terrace to Terrace method (TT method; Yoshiyama and Yanagida, 1995). To apply the TT method, it is necessary to identify the pair of the sedimentary terraces of the last glacial period and the one before last glacial period. However, there are many mountains where such terrace pairs are not recognized. Therefore, as an alternative method to the TT method, we suggest the method based on landforms and deposits of incised meandering rivers (for example, Yasue et al., 2014; Ogata et al., 2021). In this presentation, we will report the results of a survey conducted in the middle of the Oi River as part of such research.
Ogata, Manabu; King, G. E.*; Herman, F.*; Sueoka, Shigeru
no journal, ,
no abstracts in English
King, G. E.*; Wen, X.*; Bartz, M.*; Anderson, L.*; Bossin, L.*; Tsukamoto, Sumiko*; Li, Y.*; Herman, F.*; Ogata, Manabu; Sueoka, Shigeru
no journal, ,
Ogata, Manabu; King, G. E.*; Herman, F.*; Yamada, Ryuji*; Omura, Kentaro*; Sueoka, Shigeru
no journal, ,
Optically stimulated luminescence (OSL)-thermometry can be used to reconstruct the thermal structure in slowly denuded regions where infrared stimulated luminescence (IRSL) signals of samples obtained from deep boreholes are measured and evaluated with depth. Only one study had explored this approach, using a target mineral of Na-feldspar. We applied multi-OSL-thermometry to K-feldspar obtained from deep borehole core samples drilled at the Tono (MIZ-1) and Rokko regions (Kabutoyama), which are well-documented thermally stable crustal environment. For the K-feldspar obtained from the MIZ-1 core, the inverted temperatures for the IRSL50 C of the samples at a depth of
1 km (
40
C) were consistent with the in-situ temperatures. The results suggest that the application of OSL-thermometry to K-feldspar in a borehole is useful to reconstruct the palaeothermal condition. In this presentation, we will also show the results of the Kabutoyama core to draw more comprehensive conclusions.
Ogata, Manabu; Tsukahara, Yuzuko; Nishiyama, Nariaki; Komatsu, Tetsuya; Uchida, Mao; Kawamura, Makoto; Ishihara, Takanori; Nakanishi, Toshimichi*
no journal, ,
Terrace to terrace (TT) method is mainly used for estimating uplift rate on mountain areas of Japan on 10-year time scale. However, this method cannot be applied to the area with poor distribution of fluvial terraces. In such area, the method based on the emergence ages of the fluvial landform, e.g., an abandoned river valley around a cutoff spur, and the relative elevation between old and present reiver bed is expected instead of TT method. This method calculates the river-incision rate by dividing the relative elevation by the emergence age. The river-incision rate is equal to the uplift rate if the river is at equilibrium (graded stream). We are investigating the fluvial landform in the Oi River basin for verifying this method. In this presentation, we will present the incision and uplift rate estimated by feldspar OSL dating results.
Uchida, Mao; Nishiyama, Nariaki; Ogata, Manabu; Komatsu, Tetsuya; Tsukahara, Yuzuko; Ishihara, Takanori; Kawamura, Makoto; Nakanishi, Toshimichi*; Terada, Tatsuya*; Hosoya, Takashi*
no journal, ,
no abstracts in English